Biltwell grips are available in 7/8” ”. Each size number refers to the outside diameter of the bar end on the left side of your scooter. If you don’t know the O.D. of your handlebars, measure with a caliper, an open-end wrench or other device. Each set comes with two grips: one for the clutch side (small inside diameter) and one for the throttle (larger I.D.) Installing the wrong grip on either side may result in loose-fitting grips or grips that can tear and stretch too far during installation. If any of this information seems overly simplistic, it is only because we get a lot of questions from guys who say they have never installed grips. Hard to believe, but true.